This part of ISO/IEC 7816 specifies the content of the messages, commands and responses, transmitted by the interface device to the card and conversely, the structure and content of the historical bytes sent by the card during the answer to reset, the structure of files and data as seen at the interface when processing interindustry commands for interchange, etc. It does no cover the internal implementation within the card and/or the outside world. It allows further standardization of additional interindustry commands and security architecture.